The present invention relates to computers and computer networks and more specifically to a system for providing ordered transmission of messages in a computer network.
As personal computers have become a popular communication device for many users worldwide problems have arisen from the competition for network resources and for access to transmission time. One manifestation of this problem occurs when more than one communication unit attempts to transmit a signal over the same communication medium in a network. This results in contention for network resources and collisions among the competing signals.
Examples of networks exhibiting these problems are local area networks (LANs) such as Ethernet networks, metropolitan area networks (MANs), and wide area networks (WANs) such as are often used in the Internet.
There are a number of solutions to these problems in the art. U.S. Pat. No. 5,450,594 relates to enhanced collision detection in an Ethernet network. It offers a solution that is typical in the field in that it assumes that collisions are a given and then tries to provide an improved method for dealing with them. It, as in the cases of many others, does not try to prevent collisions from occurring in the first place.
U.S. Pat. No. 5,668,811 relates to a method of maintaining frame synchronization in a communication network. This is representative of many other subsequent attempted solutions in that it suggests a solution that requires the addition of expensive hardware devices, complicated algorithms and/or costly external devices to the network.
U.S. Pat. No. 4,063,220 (from the original inventors of the Ethernet) relates to a multi point data communication system with collision detection.
Most of the above approaches simply assume that there will be contention and collisions in the network and attempt to work around this accepted limitation. Thus there is a need to solve these problems by avoiding the contention/collision problems in the first place. Such solutions exist but are expensive and complicated.